What is a Patient Information Leaflet and why is it useful?
The Patient Information Leaflet (PIL) is the leaflet included in the pack with a medicine. It is written for patients and gives information about taking or using a medicine. It is possible that the leaflet in your medicine pack may differ from this version because it may have been updated since your medicine was packaged.
Below is a text only representation of the Patient Information Leaflet. The original leaflet can be viewed using the link above.
The text only version may be available in large print, Braille or audio CD. For further information call emc accessibility on 0800 198 5000. The product code(s) for this leaflet is: 04425/0746 .
Flagyl 200mg & 400mg Tablets
PACKAGE LEAFLET: INFORMATION FOR THE USER
FLAGYLTM 400 MG TABLETS
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Read all of this leaflet carefully before you start taking this medicine because it contains important information for you.
- Keep this leaflet. You may need to read it again.
- If you have further questions, please ask your doctor or pharmacist.
- This medicine has been prescribed for you only. Do not pass it on to others. It may harm them, even if their signs of illness are the same as yours.
- If you get any side effects, talk to your doctor or pharmacist. This includes any possible side effects not listed in the leaflet. See section 4.
What is in this leaflet:
1. What Flagyl is and what it is used for
2. What you need to know before you take Flagyl
3. How to take Flagyl
4. Possible side effects
5. How to store Flagyl
6. Contents of the pack and other information
1. WHAT FLAGYL IS AND WHAT IT IS USED FOR
The name of this medicine is Flagyl 400mg Tablets (called Flagyl in this leaflet). Flagyl contains a medicine called metronidazole. This belongs to a group of medicines called antibiotics.
It works by killing bacteria and parasites that cause infections in your body.
It can be used to:
- Treat infections of the blood, brain, lung, bones, genital tract, pelvic area, stomach and intestines
- Treat gum ulcers and other dental infections
- Treat infected leg ulcers and pressure sores
- Prevent infections after surgery
If you need any further information on your illness, speak to your doctor.
2. WHAT YOU NEED TO KNOW BEFORE YOU TAKE FLAGYL
Do not take Flagyl and tell your doctor if:
- You are allergic (hypersensitive) to metronidazole, nitroimidazoles (e.g. tinidazole) or any of the other ingredients of this medicine (listed in section 6).
Signs of an allergic reaction include: a rash, swallowing or breathing problems, swelling of your lips, face, throat or tongue.
Do not take Flagyl if any of the above apply to you. If you are not sure, talk to your doctor or pharmacist before taking Flagyl.
Warnings and precautions
Talk to your doctor or pharmacist before taking Flagyl if:
- You have or have ever had a liver problem
- You are having kidney dialysis (see section 3: ‘People having kidney dialysis’)
- You have a disease of the nervous system
If you are not sure if any of the above apply to you, talk to your doctor or pharmacist before taking your medicine. Do this even if they have applied in the past.
Cases of severe liver toxicity/acute liver failure, including cases with a fatal outcome, in patients with Cockayne syndrome have been reported with Flagyl. If you are affected by Cockayne syndrome, your doctor should also monitor your liver function frequently while you are being treated with Flagyl and afterwards.
Serious skin reactions including Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN), acute generalised exanthematous pustulosis (AGEP) have been reported with the use of Flagyl.
- SJS/TEN can appear initially as reddish target-like spots or circular patches often with central blisters on the trunk. Also, ulcers of the mouth, throat, nose, genitals and eyes (red and swollen eyes) can occur. These serious skin rashes are often preceded by fever and/or flu-like symptoms. The rashes may progress to widespread peeling of the skin and life-threatening complications or be fatal.
- AGEP appears at the initiation of treatment as a red, scaly widespread rash with bumps under the skin and blisters accompanied by fever. The most common location: mainly localised on the skin folds, trunk, and upper extremities.
The highest risk for occurrence of serious skin reactions is within one week, typically, within 48 hours after start of treatment. If you develop a serious rash or another of these skin symptoms, stop taking Flagyl and contact your doctor or seek medical attention immediately.
Tell your doctor immediately and stop taking Flagyl if you develop: stomach pain, anorexia, nausea, vomiting, fever, malaise, fatigue, jaundice, dark urine, putty or mastic coloured stools or itching.
Other medicines and Flagyl
Tell your doctor or pharmacist if you are taking, have recently taken or might take any other medicines. This includes medicines obtained without a prescription, including herbal medicines. This is because Flagyl can affect the way some other medicines work. Also, some other medicines can affect the way Flagyl works.
In particular tell your doctor if you are taking any of the following medicines:
- Medicines used to thin the blood such as warfarin
- Lithium for mental illness
- Phenobarbital or phenytoin for epilepsy
- 5 fluorouracil for cancer
- Busulfan for leukaemia (cancer of the blood cells)
- Ciclosporin – to prevent the rejection of organs after transplant
- Disulfiram for alcoholism
If you are not sure, talk to your doctor or pharmacist before taking Flagyl.
Flagyl with food, drink and alcohol
Do not drink any alcohol while you are taking Flagyl and for 48 hours after finishing your course. Drinking alcohol while using Flagyl might cause unpleasant side effects, such as feeling sick (nausea), being sick (vomiting), stomach pain, hot flushes, very fast or uneven heartbeat (palpitations) and headache.
Pregnancy and breast-feeding
Tell your doctor before using Flagyl if:
- You are pregnant, might become pregnant or think you may be pregnant. Flagyl should not be taken during pregnancy unless considered absolutely necessary.
- You are breast-feeding. It is better not to take Flagyl if you are breast-feeding. This is because small amounts may pass into the mother’s milk.
If you are pregnant or breast-feeding, think you may be pregnant or are planning to have a baby, ask your doctor or pharmacist for advice before taking any medicine
Driving and using machines
While taking Flagyl you may feel sleepy, dizzy, confused, see or hear things that are not there (hallucinations), have fits (convulsions) or temporary eyesight problems (such as blurred or double vision). If this happens, do not drive or use any machinery or tools.
Your doctor may wish to carry out some tests if you have been using this medicine for more than 10 days.
3. HOW TO TAKE FLAGYL
Taking your medicine
Always take this medicine exactly as your doctor or pharmacist has told you. It is important to finish a full course of treatment. The length of a course will depend on your needs and the illness being treated.
Check with your doctor or pharmacist if you are not sure.
- Swallow the tablets whole with a drink of water
- Do not crush or chew the tablets
- Take these tablets during or just after a meal
- The dose of Flagyl will depend on your needs and the illness being treated
- The length of your treatment will depend on the type of illness you have and how bad it is
The usual dose for adults and children is given below:
To treat bacterial infection
- The initial dose is 800mg
- After 8 hours take another dose of 400mg and repeat this dose every 8 hours
- Your doctor will work out how much your child should take depending on their weight
- Repeat the dose every 8 hours
- If your child is a baby under 8 weeks of age, your doctor will give them one daily dose or two separate doses 12 hourly
To prevent infections from happening after surgery
- Start taking Flagyl Tablets 24 hours before your operation
- Take 400 mg of Flagyl every 8 hours
- After the operation you may be given Flagyl either through a drip into a vein or rectally as a suppository until you are able to take tablets again
- Give your child Flagyl Tablets 1-2 hours before their operation
- Your doctor will work out how much your child should take depending on their weight
- After the operation your child may be given Flagyl either through a drip into a vein or rectally as a suppository until they are able to take tablets again
Other types of infections
For treatment of other infections caused by parasites and some bacteria your doctor will decide how much Flagyl you need to take and how often. This will depend on your illness and how bad it is. The pharmacist’s label on the packaging will tell you how many tablets to take and how often to take them.
People having kidney dialysis
Kidney dialysis removes Flagyl from your blood. If you are having kidney dialysis you must take this medicine after your dialysis treatment.
People with liver problems
Your doctor may tell you to use a lower dose or to take the medicine less often.
If you take more Flagyl than you should
If you take more Flagyl than you should, tell your doctor or go to your nearest hospital casualty department straight away. Take the pack and any tablets left with you. This is so the doctor knows what you have taken.
If you forget to take Flagyl
If you forget to take Flagyl, take it as soon as you remember. However, if it is almost time for your next dose, skip the missed dose. Do not take a double dose to make up for a forgotten dose.
If you have any further questions on the use of this medicine, ask your doctor or pharmacist.
4. POSSIBLE SIDE EFFECTS
Like all medicines, this medicine can cause side effects, although not everybody gets them.
Stop taking Flagyl and see a doctor or go to a hospital straight away if:
- You get swelling of the hands, feet, ankles, face, lips or throat which may cause difficulty in swallowing or breathing. You could also notice an itchy, lumpy rash (hives) or nettle rash (urticaria). This may mean you are having an allergic reaction to Flagyl.
- A serious but very rare side effect is a brain disease (encephalopathy). Symptoms vary but you might get a fever, stiff neck, headache, see or hear things that aren’t there. You might also have problems using your arms and legs, problems with speaking or feel confused.
- You develop skin rashes including Stevens-Johnson syndrome or toxic epidermal necrolysis. These can appear as reddish target-like spots or circular patches often with central blisters on the trunk, skin peeling, ulcers of the mouth, throat, nose, genitals and eyes and can be preceded by fever and flu-like symptoms. Stop using Flagyl if you develop these symptoms and contact your doctor or seek medical attention immediately. See also section 2.
- You develop a red, scaly widespread rash with bumps under the skin and blisters accompanied by fever at the initiation of treatment (acute generalised exanthematous pustulosis). Stop using Flagyl if you develop these symptoms and contact your doctor or seek medical attention immediately. See also section 2.
Talk to your doctor straight away if you notice the following side effects.
- Yellowing of the skin and eyes. This could be due to a liver problem (jaundice).
- Unexpected infections, mouth ulcers, bruising, bleeding gums, or severe tiredness. This could be caused by a blood problem.
- Severe stomach pain which may reach through to your back (pancreatitis)
Tell your doctor or pharmacist if you notice any of the following side effects:
Very rare (affects less than 1 in 10 000 people)
- Fits (convulsions)
- Mental problems such as feeling confused and seeing or hearing things that are not there (hallucinations)
- Problems with your eyesight such as blurred or double vision
- Skin rash or flushing
- Darkening of the urine
- Feeling sleepy or dizzy
- Pains in the muscles or joints
- Liver problems including life-threatening liver failure (hepatocellular liver injury)
Not known (frequency cannot be estimated from the available data)
- Numbness, tingling, pain, or a feeling of weakness, in the arms or legs
- Unpleasant taste in the mouth
- Furred tongue
- Feeling sick (nausea), being sick (vomiting), upset stomach, stomach pain or diarrhoea
- Loss of appetite
- Feeling depressed
- Pain in your eyes (optic neuritis)
- A group of symptoms together including: fever, nausea, vomiting, headache, stiff neck and extreme sensitivity to bright light. This may be caused by an inflammation of the membranes that cover the brain and spinal cord (meningitis)
- Hearing impairment/hearing loss
- Ringing in the ears (tinnitus)
- You get a rash or skin discolouration with or without raised areas which often reoccurs at the same location each time the drug is taken
Reporting of side effects
If you get any side effects, talk to your doctor, pharmacist or nurse. This includes any possible side effects not listed in this leaflet. You can also report side effects directly via the Yellow Card Scheme at: www.mhra.gov.uk/yellowcard or seach for MHRA Yellow card in the Google Play or Apple App Store.
By reporting side effects you can help provide more information on the safety of this medicine.
5. HOW TO STORE FLAGYL
Keep your medicine in a safe place and out of the sight and reach of children.
Store below 30º C in the original packaging (protect from light). Do not use this medicine after the expiry date which is stated on the pack. The expiry date refers to the last day of that month. Do not throw away any medicines via wastewater or household waste. Ask your pharmacist how to throw away any medicines you no longer use. These measures will help protect the environment.
6. CONTENTS OF THE PACK AND OTHER INFORMATION
What Flagyl Tablets contain
Each tablet contains 400mg of metronidazole as the active substance.
Other ingredients are: calcium hydrogen phosphate (E341), starch maize, povidone K30 (E1201) and magnesium stearate. The coating of the tablets contains: Pharmacoat 615 (E464) and Macrogol 400.
What Flagyl Tablets look like and contents of the pack
Flagyl 400mg Tablets are white to off-white biconvex film coated tablets with ‘Flagyl 400’ printed on one side.
Flagyl 400mg Tablets are available in aluminium/plastic blister packs of 14 tablets and HDPE bottles of 100 tablets.
Marketing Authorisation Holder and Manufacturer:
Marketing Authorisation Holder
410 Thames Valley Park Drive
Avda. Leganés, 62
Alcorcón 28923 (Madrid)
This leaflet does not contain all the information about your medicine. If you have any questions or are not sure about anything, ask your doctor or pharmacist.
This leaflet was last revised in March 2021
© Sanofi, 1984 - 2021